Simple, advanced or qualified e-signature: which is enough?
The three eIDAS levels in plain words, where QuoteBill's simple signature fits, when it is enough, and how Korea, Japan and Germany draw the line.
Three levels, one regulation
The EU’s eIDAS Regulation (No 910/2014) sorts electronic signatures into three levels. A simple electronic signature is any electronic data a person attaches to a document and uses to sign (Article 3(10)). An advanced electronic signature must also meet Article 26: uniquely linked to the signer, able to identify the signer, created under the signer’s sole control, and linked to the document so that any later change is detectable.
A qualified electronic signature is an advanced signature made with a qualified signature creation device and based on a qualified certificate (Article 3(12)). Under Article 25, no electronic signature may be denied legal effect or admissibility as evidence solely because it is electronic or not qualified (Article 25(1)), and only a qualified one has the equivalent legal effect of a handwritten signature (Article 25(2)).
Where QuoteBill fits
QuoteBill creates a simple electronic signature with an audit trail. It is not a qualified or advanced electronic signature, and QuoteBill does not verify who signs: it records the use of the link and access code the sender delivered, freezes the text with its SHA-256 fingerprint, and issues a signature certificate that is its own record, not one from a trust service provider. Its times come from a database clock, not a qualified time stamp. General information, not legal advice.
When a simple signature is enough
Where no law prescribes a form, the parties choose one; a simple signature with good evidence serves most service, supply, freelance and confidentiality agreements. It is not enough where a law demands written form, a witness, a notary or a qualified signature. Examples, not a complete list:
- Wills: Korea, Japan and Germany require a holographic will to be handwritten.
- Guarantees: in Korea a guarantee declared in electronic form has no effect unless the guarantor gives it in its own business (Civil Act art. 428-2; Framework Act on Electronic Documents art. 4(2)); in Germany the electronic form is excluded (§ 766 BGB).
- Employment in Germany: a fixed-term clause needs written form (§ 14(4) TzBfG), as do notice of termination and a termination agreement, where electronic form is excluded (§ 623 BGB).
Korea: one rule, no levels
Korea’s Electronic Signature Act has no levels. An electronic signature is not denied effect as a signature or seal only because it is electronic (Article 3(1)), and it has that effect where a law or the parties’ agreement chose one (Article 3(2)). The current Article 3 privileges no kind of signature, so what a signature proves comes down to the evidence behind it.
Japan: who applies the signature
Japan’s Electronic Signature Act defines an electronic signature as a measure that shows who made the information and lets any alteration be detected (Article 2(1)). Article 3 presumes an electronic record authentic only when the signature is one that only the person can make. Services where the signer uses their own certificate are called 当事者型; where the provider signs with its own key on the signer’s instruction, 事業者署名型 or 立会人型.
Government Q&As (2020-07-17 on Article 2; 2020-09-04, revised 2024-01-09, on Article 3) say a provider-signed service can be the user’s own signature and can earn the presumption where both its user-facing and internal processes show sufficient uniqueness (for example two-factor authentication), decided by a court case by case. QuoteBill does not claim the Article 3 presumption.
Germany: written, electronic and text form
Where a German statute requires written form, the document must be signed by hand (§ 126(1) BGB). Electronic form may replace it unless the law says otherwise (§ 126(3)), and it means a qualified electronic signature (§ 126a BGB). Text form (§ 126b BGB) needs only a readable declaration on a durable medium naming the person, which a simple signature can satisfy. Where the parties themselves agreed written form, telecommunicative transmission suffices in case of doubt (§ 127(2) BGB).
Which level do you need?
Pick the level by the document and the law of the country that governs it; when in doubt, ask a lawyer who knows both:
- Simple signature with an audit trail: everyday business agreements with no statutory form.
- Advanced or qualified signature: where a law or the other party requires a signature that identifies the signer, or a statutory written form is replaced electronically (§ 126a BGB).
- Another form altogether: wills, notarised deeds, private guarantees.
Sources
- EUR-Lex: Regulation (EU) No 910/2014 (eIDAS), Articles 3, 25 and 26
- Korea Law Information Center: Electronic Signature Act, Article 3
- e-Gov: Act on Electronic Signatures and Certification Business, Articles 2 and 3
- Ministry of Justice (Japan): Q&A on Article 3 for provider-signed e-contract services (2020, revised 2024)
- German Civil Code (BGB), § 126a: electronic form
- German Civil Code (BGB), § 127: agreed form
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